PURPOSE
Purpose of this commit is to add a company field on test mail models used to
replicate ticket / project behavior (``mail.test.ticket`` and ``mail.test.
container``).
SPECIFICATIONS
To avoid messing with existing tests and ease comparison through all Odoo
versions (notably performance) this is done by adding new models inheriting
from current mail models. A company_id field is added as well as MC rules.
Those models will be used to add tests for mail thread behavior in a multi
company environment (aliases management, performance, emails and notification
layouts, ...).
In this commit we also update ACLs for ticket-like models to add rules for
portal users, based on followers. This mimics classic rules from Odoo used
notably in a light project-like environment. This allows to test a bit more
in details recipients, access tokens, links in emails, ...
Task-2673913 (TestMail: Cleanup and improve test coverage)
Part-of: odoo/odoo#86393